Method for recovering valuable materials from batteries

Abstract

A method of recycling batteries includes steps of: shredding the batteries to generate a shredded battery feed material, wetting the shredded battery feed material with an ammonia carbonate lixiviant to generate a slurry, separating the battery feed material in the slurry into a relatively light fraction material slurry and a relatively heavy fraction material slurry, processing the relatively light fraction material slurry in a first counter current ammoniacal leaching and decanting circuit to produce a first pregnant leaching solution including a soluble lithium (Li) component, and processing the relatively heavy fraction material slurry in a second counter current ammoniacal leaching and decanting circuit to produce a second pregnant leaching solution including, if present in the batteries, soluble nickel (Ni), cobalt (Co), zinc (Zn) and copper (Cu) components and insoluble graphite, iron (Fe), aluminum (Al), manganese (Mn) and rare earth element (REEs) components

What is claimed: 
     
         1 . A method of recycling batteries, comprising:
 shredding the batteries to generate a shredded battery feed material;   wetting the shredded battery feed material with an ammonia carbonate lixiviant to generate a slurry;   separating the battery feed material in the slurry into a relatively light fraction material slurry and a relatively heavy fraction material slurry;   processing the relatively light fraction material slurry in a first counter current ammoniacal leaching and decanting circuit to produce a first pregnant leaching solution including a soluble lithium (Li) component; and   processing the relatively heavy fraction material slurry in a second counter current ammoniacal leaching and decanting circuit to produce a second pregnant leaching solution including, if present in the batteries, soluble nickel (Ni), cobalt (Co), zinc (Zn) and copper (Cu) components and insoluble graphite, iron (Fe), aluminum (Al), manganese (Mn) and rare earth element (REEs) components.   
     
     
         2 . The method of  claim 1 , further including removing ammonia from the first pregnant leaching solution. 
     
     
         3 . The method of  claim 2 , wherein the removing of the ammonia from the first pregnant leaching solution is performed by first heating the first pregnant leaching solution to evaporate the ammonia and then reabsorbing the evaporated ammonia in water. 
     
     
         4 . The method of  claim 3 , further including precipitating the lithium component from the first pregnant leaching solution as lithium carbonate in a lithium precipitation circuit and filtering the lithium carbonate from the first pregnant leaching solution. 
     
     
         5 . The method of  claim 4 , including separating solid plastics from the first pregnant leaching solution before the precipitating of the lithium component. 
     
     
         6 . The method of  claim 5 , further including removing ammonia from the second pregnant leaching solution by first heating the lixiviant to evaporate the ammonia and then reabsorbing the evaporated ammonia in cooling water. 
     
     
         7 . The method of  claim 6 , further including separating graphite from the second pregnant leaching solution before the removing of the ammonia. 
     
     
         8 . The method of  claim 7 , including using floatation for the separating of the graphite from the heavy fraction material in the lixiviant. 
     
     
         9 . The method of  claim 7 , further including filtering or settling solid materials from the second pregnant leaching solution. 
     
     
         10 . The method of  claim 9 , further including using magnetic separation to separate iron-rich components from other solid materials including aluminum, manganese and rare earth element components. 
     
     
         11 . The method of  claim 10 , including removing further ammonia from the second pregnant leaching solution to lower the pH to a value of between about 7 and about 10.5 and then subjecting the second pregnant leaching solution to solvent extraction to sequentially extract the nickel component, the cobalt component, the copper component and the zinc component. 
     
     
         12 . The method of  claim 11 , including (a) stripping the nickel component from the second pregnant leaching solution with acid, (b) producing nickel hydroxide from the nickel component extracted from the second pregnant leaching solution and then (c) recovering the nickel hydroxide by filtering. 
     
     
         13 . The method of  claim 11 , including electrowinning cobalt metal from the cobalt component extracted from the second pregnant leaching solution. 
     
     
         14 . The method of  claim 11 , including stripping the copper component and the zinc component from the second leaching solution with acid and electrowinning copper and zinc metal from the copper component and the zinc component extracted from the second leaching solution. 
     
     
         15 . The method of  claim 1 , further including subjecting lithium ion batteries to reductive roasting prior to the wetting of the shredded battery feed material with an ammonia carbonate lixiviant. 
     
     
         16 . The method of  claim 15 , wherein the reductive roasting includes heating the lithium ion batteries to a temperature of between about 450° C. and 850° C. for a duration of time until the lithium ion batteries cease generating gasses. 
     
     
         17 . The method of  claim 15 , further including recirculating the first pregnant leaching solution to the first counter current ammoniacal leaching and decanting circuit following the filtering of the lithium carbonate from the first pregnant leaching solution. 
     
     
         18 . The method of  claim 17 , further including recirculating the second pregnant leaching solution to the lithium precipitating circuit following the filtering of the solid materials from the second pregnant leaching solution. 
     
     
         19 . The method of  claim 18 , further including recirculating the second pregnant leaching solution to the lithium precipitating circuit following the filtering of the nickel hydroxide from the second pregnant leaching solution. 
     
     
         20 . The method of  claim 19 , further including returning the ammonia removed from the first and second pregnant leaching solutions to the first and second counter current ammoniacal leaching and decanting circuits.